Electric pump

Abstract

To provide an electric pump having a structure capable of reducing man-hours and time required for manufacturing.SOLUTION: An electric pump according to an example embodiment of the present disclosure includes a rotor rotatable about a central axis, a stator located radially outside the rotor, a pump portion connected to one side of the rotor in an axial direction, a circuit board located on the other side of the stator in the axial direction, a housing having a pump accommodation portion that accommodates the pump portion therein, a cover that covers the circuit board from the other side in the axial direction, and a mold resin portion 70 that is in contact with at least a part of the housing and at least a part of the cover and connects the housing 50 and the cover 61.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an electric pump. [Background technology]

[0002] BACKGROUND ART An electric pump is known that includes a motor housing, a pump housing, and a driver case cover, which are separate members (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2012 / 042971 Summary of the Invention [Problem to be solved by the invention]

[0004] When assembling the electric pump described above, workers must secure the pump housing to the motor housing and secure the cover to the driver case that is integral with the motor housing, which increases the number of steps and time required to manufacture the electric pump.

[0005] In view of the above circumstances, an object of the present invention is to provide an electric pump having a structure that can reduce the number of steps and time required for manufacturing. [Means for solving the problem]

[0006] One aspect of the electric pump of the present invention comprises a rotor rotatable about a central axis, a stator located radially outside the rotor, a pump section connected to one axial side of the rotor, a circuit board located on the other axial side of the stator, a housing having a pump accommodating section that accommodates the pump section therein, a cover that covers the circuit board from the other axial side, and a molded resin section that contacts at least a portion of the housing and at least a portion of the cover and connects the housing and the cover. [Effects of the Invention]

[0007] According to one aspect of the present invention, the number of steps and time required to manufacture an electric pump can be reduced. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing an electric pump according to a first embodiment. [Figure 2] FIG. 2 is a cross-sectional view showing the electric pump according to the first embodiment. [Figure 3] FIG. 3 is a perspective view showing the stator assembly in the first embodiment. [Figure 4] FIG. 4 is a cross-sectional view showing a part of the electric pump according to the first embodiment. [Figure 5] FIG. 5 is a perspective view showing a housing in the first embodiment. [Figure 6] FIG. 6 is a perspective view showing the cover assembly in the first embodiment. [Figure 7] FIG. 7 is a cross-sectional view showing a part of the electric pump according to the first embodiment, illustrating the third annular protrusion. [Figure 8] FIG. 8 is a cross-sectional view showing a part of a manufacturing procedure for the electric pump according to the first embodiment. [Figure 9] FIG. 9 is a cross-sectional view showing another part of the manufacturing procedure of the electric pump according to the first embodiment. [Figure 10]FIG. 10 is a cross-sectional view showing still another part of the manufacturing procedure of the electric pump according to the first embodiment. [Figure 11] FIG. 11 is a cross-sectional view showing a part of a procedure for molding the molded resin portion in the first embodiment. [Figure 12] FIG. 12 is a cross-sectional view showing a part of the electric pump according to the second embodiment. [Figure 13] FIG. 13 is a cross-sectional view showing a part of the electric pump according to the third embodiment. [Figure 14] FIG. 14 is a cross-sectional view showing a part of the electric pump according to the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Each figure shows an imaginary central axis J of a pump according to an embodiment described below. In the following description, the axial direction of the central axis J will be simply referred to as the "axial direction," the radial direction about the central axis J will be simply referred to as the "radial direction," and the circumferential direction about the central axis J will be simply referred to as the "circumferential direction." The Z axis shown in each figure indicates the direction in which the central axis J extends. In the following description, the side of the axial direction toward which the arrow of the Z axis points (+Z side) will be referred to as the "upper side," and the side of the axial direction opposite to the side toward which the arrow of the Z axis points (-Z side) will be referred to as the "lower side."

[0010] In the following embodiments, the lower side corresponds to the “one axial side,” and the upper side corresponds to the “other axial side.” Note that the terms “upper side” and “lower side” are simply names used to describe the relative positional relationship of each part, and the actual positional relationship may be one other than the positional relationship indicated by these names.

[0011] First Embodiment 1 and 2, the electric pump 100 of this embodiment is a water pump that delivers water. As shown in Fig. 2, the electric pump 100 of this embodiment includes a rotor 10, a stator assembly 20, a pump section 40, a housing 50, a cover assembly 60, a molded resin section 70, a circuit board 95, and a plurality of electronic components 96.

[0012] The rotor 10 is rotatable about a central axis J. The rotor 10 has a rotor core 11, a magnet 12, a first rotor resin portion 13, a second rotor resin portion 14, and a bearing portion 15. The rotor core 11 is annular and surrounds the central axis J. The magnet 12 is fixed to a radially outer surface of the rotor core 11. For example, a plurality of magnets 12 are provided at intervals in the circumferential direction.

[0013] The first rotor resin portion 13 has a generally cylindrical shape that surrounds the central axis J and extends in the axial direction. The first rotor resin portion 13 covers the rotor core 11 and the multiple magnets 12 from the radially outer side and both axially opposite sides. The rotor core 11 and the multiple magnets 12 are embedded in the first rotor resin portion 13. In this embodiment, the first rotor resin portion 13 is made by insert molding using the rotor core 11 and the multiple magnets 12 as insert members.

[0014] The second rotor resin portion 14 has a generally cylindrical shape that surrounds the central axis J and extends in the axial direction. The second rotor resin portion 14 is located radially inside the rotor core 11. The second rotor resin portion 14 covers the radially inside surface of the rotor core 11. The second rotor resin portion 14 has a portion that axially sandwiches the first rotor resin portion 13. The second rotor resin portion 14 is fixed to the first rotor resin portion 13. In this embodiment, the second rotor resin portion 14 is produced by insert molding using a molded body including the rotor core 11, the plurality of magnets 12, and the first rotor resin portion 13, which are integrally molded by insert molding, and the bearing portion 15 as an insert member.

[0015] The bearing portion 15 is cylindrical, through which the fixed shaft 30 (described later) passes in the axial direction. In this embodiment, the bearing portion 15 is substantially cylindrical, surrounding the central axis J and extending in the axial direction. The bearing portion 15 is a portion that is rotatably supported by the fixed shaft 30. The bearing portion 15 is located radially inside the second rotor resin portion 14. The outer peripheral surface of the bearing portion 15 is fixed to the inner peripheral surface of the second rotor resin portion 14. The bearing portion 15 is made of, for example, resin. The bearing portion 15 is open on both sides in the axial direction.

[0016] The stator assembly 20 has a stator 20a, a stator resin portion 24, and a fixed shaft 30. In other words, the electric pump 100 is equipped with the stator 20a, the stator resin portion 24, and the fixed shaft 30. The stator 20a is located radially outward of the rotor 10. The stator 20a surrounds the rotor 10. The stator 20a faces the rotor 10 in the radial direction via a gap and part of the resin that constitutes the stator resin portion 24. The stator 20a has a stator core 21, an insulator 22 attached to the stator core 21, and a plurality of coils 23 attached to the stator core 21 via the insulator 22.

[0017] The stator core 21 is located radially outward of the rotor core 11 and the plurality of magnets 12 and surrounds the rotor core 11 and the plurality of magnets 12. The stator core 21 is formed, for example, by stacking a plurality of plate members in the axial direction. The plurality of plate members constituting the stator core 21 are, for example, electromagnetic steel plates. The stator core 21 has an annular core back 21a that surrounds the rotor 10 and a plurality of teeth 21b that extend radially inward from the core back 21a. The plurality of teeth 21b are arranged at intervals in the circumferential direction. The plurality of coils 23 are attached to the plurality of teeth 21b via insulators 22.

[0018] The fixed shaft 30 extends in the axial direction. More specifically, the fixed shaft 30 has a generally cylindrical shape extending in the axial direction about the central axis J. The fixed shaft 30 is located radially inside the bearing portion 15 of the rotor 10. The fixed shaft 30 is passed through the axial direction radially inside the bearing portion 15. The fixed shaft 30 protrudes on both sides in the axial direction beyond the bearing portion 15. The fixed shaft 30 is clearance-fitted into the radially inside of the bearing portion 15. The fixed shaft 30 supports the inner circumferential surface of the bearing portion 15, thereby rotatably supporting the rotor 10.

[0019] The upper end of the fixed shaft 30 is embedded in a partition wall portion 24a (described later) of the stator resin portion 24. The upper end of the fixed shaft 30 is held in the partition wall portion 24a. The fixed shaft 30 extends downward from the partition wall portion 24a. The lower end of the fixed shaft 30 is located below a rotor accommodating portion 24r (described later). A pair of shaft recesses 31 are provided in the portion of the fixed shaft 30 embedded in the partition wall portion 24a, with the central axis J sandwiched between them in the radial direction. As part of the resin that constitutes the partition wall portion 24a is positioned within the pair of shaft recesses 31, the fixed shaft 30 is prevented from coming off the partition wall portion 24a.

[0020] The stator resin portion 24 is made of resin. At least a portion of the stator 20a is embedded in the stator resin portion 24. In this embodiment, the entire stator 20a is embedded in the stator resin portion 24. The stator 20a and the fixed shaft 30 are connected by the stator resin portion 24. The stator resin portion 24 has a portion that covers the stator 20a from the radially inner side, a portion that covers the stator 20a from the radially outer side, a portion that covers the stator 20a from above, and a portion that covers the stator 20a from below. In this embodiment, the entire outer circumferential surface of the stator 20a is covered by the stator resin portion 24 and is not exposed to the outside of the stator assembly 20.

[0021] The stator resin portion 24 has a stator resin main body portion 24s. The stator resin main body portion 24s is cylindrical and surrounds the central axis J, opening downward. In this embodiment, the stator resin main body portion 24s is generally cylindrical and has a center on the central axis J, opening downward. The stator resin main body portion 24s has a partition wall portion 24a and a first annular resin portion 24b. That is, the stator resin portion 24 has the partition wall portion 24a and the first annular resin portion 24b.

[0022] The partition wall 24a is a wall that axially separates the internal space of a rotor accommodating portion 24r (described later) from the internal space of a substrate accommodating portion 90 (described later). The partition wall 24a extends in the radial direction. A central axis J passes through the partition wall 24a. As shown in FIG. 3, in this embodiment, the partition wall 24a has a circular shape whose center coincides with the central axis J when viewed in the axial direction.

[0023] The first annular resin portion 24b has an annular shape surrounding the central axis J. In the present embodiment, the first annular resin portion 24b has a substantially cylindrical shape centered on the central axis J. As shown in FIG. 2, the first annular resin portion 24b opens downward. An upper end of the first annular resin portion 24b is closed by the partition wall portion 24a.

[0024] At least a portion of the stator 20a is embedded in the first annular resin portion 24b. In this embodiment, the entire stator 20a is embedded in the first annular resin portion 24b. The first annular resin portion 24b has a portion that covers the stator 20a from the radially inner side, a portion that covers the stator 20a from the radially outer side, a portion that covers the stator 20a from above, and a portion that covers the stator 20a from below. In other words, the stator resin main body portion 24s has a portion that covers the stator 20a from above. In this embodiment, the first annular resin portion 24b covers the radially outer surface of the stator 20a over the entire circumference around the central axis J. The radially outer surface of the stator 20a includes the radially outer surface of the stator core 21 and the radially outer surface of the insulator 22. The radially outer surface of the stator core 21 is the radially outer surface of the core back 21a.

[0025] The radially outer edge of the partition wall portion 24a is connected to the radially inner edge of the upper end of the first annular resin portion 24b. The upper surfaces of the first annular resin portion 24b and the partition wall portion 24a are located at the same position in the axial direction and are connected to each other without any steps. In this embodiment, the upper surface of the stator resin main body portion 24s is defined by the upper surface of the partition wall portion 24a and the upper surface of the first annular resin portion 24b.

[0026] As shown in FIG. 3 , the first annular resin portion 24b has a large diameter portion 24c and a small diameter portion 24d. The upper end of the large diameter portion 24c is the upper end of the first annular resin portion 24b. The small diameter portion 24d is located below the large diameter portion 24c. The upper end of the small diameter portion 24d is connected to the lower end of the large diameter portion 24c. The lower end of the small diameter portion 24d is the lower end of the first annular resin portion 24b. The outer diameter of the small diameter portion 24d is smaller than the outer diameter of the large diameter portion 24c. A fourth step surface 24g facing downward is provided axially between the radially outer surface of the large diameter portion 24c and the radially outer surface of the small diameter portion 24d. The fourth step surface 24g is annular and surrounds the central axis J. More specifically, the fourth step surface 24g is annular and has a center coincident with the central axis J when viewed in the axial direction.

[0027] The stator resin body 24s has an annular groove 24f recessed downward from the upper surface of the stator resin body 24s. In this embodiment, the annular groove 24f is recessed downward from the radially outer edge of the upper surface of the stator resin body 24s. In this embodiment, the annular groove 24f is provided on the upper surface of the first annular resin portion 24b, i.e., the upper surface of the large diameter portion 24c. The annular groove 24f is provided radially inward and spaced apart from the radially outer surface of the large diameter portion 24c. The annular groove 24f is annular in shape surrounding the central axis J. In this embodiment, the annular groove 24f is annular in shape with its center coinciding with the central axis J when viewed in the axial direction.

[0028] The stator resin portion 24 has a recess 24e recessed radially inward on the radially outer surface of the first annular resin portion 24b. In this embodiment, the recess 24e is provided on the radially outer surface of the large diameter portion 24c. The recess 24e extends in the axial direction. The recess 24e extends from the upper end of the large diameter portion 24c to the lower end of the large diameter portion 24c. The recess 24e is open on both axial sides. A plurality of the recesses 24e are provided at intervals in the circumferential direction. For example, three recesses 24e are provided.

[0029] The stator resin portion 24 has ribs 26 that protrude radially outward from the radially outer surface of the first annular resin portion 24b. In this embodiment, the ribs 26 protrude radially outward from the radially outer surface of the large diameter portion 24c. The ribs 26 extend in the axial direction. The ribs 26 extend from the upper end of the large diameter portion 24c to the lower end of the large diameter portion 24c. Although not shown, a plurality of ribs 26 are provided at intervals in the circumferential direction. Each rib 26 is provided, for example, in the circumferential center between circumferentially adjacent recesses 24e.

[0030] The stator resin portion 24 has a board support portion 27. The board support portion 27 protrudes upward from the upper surface of the stator resin main body portion 24s. In this embodiment, the board support portion 27 protrudes upward from the upper surface of the first annular resin portion 24b. Note that the board support portion 27 may also protrude upward from the upper surface of the partition wall portion 24a. As shown in FIG. 2, the board support portion 27 supports the circuit board 95 from below. The board support portion 27 is fixed to the circuit board 95.

[0031] The board support portion 27 has a first portion 27a and a second portion 27b. A lower end of the first portion 27a is connected to an upper surface of the stator resin main body portion 24s. As shown in FIG. 3, the first portion 27a has a cylindrical shape extending in the axial direction. The second portion 27b is located above the first portion 27a. A lower end of the second portion 27b is connected to an upper end of the first portion 27a. Before the board support portion 27 is fixed to the circuit board 95, the second portion 27b has a generally cylindrical shape with an outer diameter smaller than that of the first portion 27a. As shown in FIG. 2, the second portion 27b is passed through a hole 95a provided in the circuit board 95 in the axial direction. A portion of the second portion 27b located above the circuit board 95 is melted by heat, for example, and welded to the upper surface of the circuit board 95. 2, a welded portion 27c formed by melting a portion of the second portion 27b and welding it to the upper surface of the circuit board 95 is indicated by a two-dot chain line. Note that the portion of the second portion 27b does not have to be welded to the circuit board 95. As shown in FIG. 3, a plurality of board support portions 27 are provided at intervals in the circumferential direction. In this embodiment, three board support portions 27 are provided.

[0032] The stator resin portion 24 has a second annular protrusion 25. The second annular protrusion 25 protrudes upward from a portion of the upper surface of the stator resin main body portion 24s that is located radially outward from the annular groove 24f. As shown in FIG. 4, the second annular protrusion 25 protrudes upward from a portion of the upper surface of the stator resin main body portion 24s that is located radially outward from a cover cylindrical portion 61b (described later). As shown in FIG. 3, the second annular protrusion 25 has an annular shape surrounding the central axis J. In this embodiment, the second annular protrusion 25 has a circular ring shape whose center coincides with the central axis J when viewed in the axial direction. As shown in FIG. 4, the second annular protrusion 25 has a generally triangular shape that is convex upward in a cross section perpendicular to the circumferential direction. The second annular protrusion 25 is embedded in the molded resin portion 70.

[0033] As shown in FIG. 3 , the stator assembly 20 has conductive members 28. The conductive members 28 are made of metal. A plurality of conductive members 28 are provided at intervals in the circumferential direction. In this embodiment, three conductive members 28 are provided. A portion of each conductive member 28 is embedded in the stator resin main body 24s. Each conductive member 28 is held by the stator resin main body 24s. Each conductive member 28 protrudes upward from the upper surface of the stator resin main body 24s. Each conductive member 28 has a base 28a and a connection terminal 28b. A portion of the base 28a is embedded in the stator resin main body 24s. An upper portion of the base 28a protrudes upward from the upper surface of the stator resin main body 24s. Although not shown, the portion of the base 28a embedded in the stator resin main body 24s is electrically connected to the coil 23. The connection terminal 28b protrudes upward from the base 28a. Two connection terminals 28b are provided for each conductive member 28. In this embodiment, the connection terminals 28b are press-fit terminals. The connection terminals 28b are press-fit into holes 95c provided in the circuit board 95, and are electrically connected to the circuit board 95. This electrically connects the coil 23 and the circuit board 95 via the conductive members 28.

[0034] As shown in FIG. 2, the stator assembly 20 has a rotor accommodating portion 24r that accommodates the rotor 10 therein. The rotor accommodating portion 24r is composed of a portion of the stator resin portion 24 that covers the stator 20a from the radially inner side, and a partition wall portion 24a. The rotor accommodating portion 24r is cylindrical and surrounds the central axis J, opening downward. In this embodiment, the rotor accommodating portion 24r is substantially cylindrical and centered on the central axis J, opening downward. The upper wall portion of the rotor accommodating portion 24r is composed of the partition wall portion 24a. The stator assembly 20 is produced, for example, by molding the stator resin portion 24 by insert molding, using the stator 20a, the fixed shaft 30, and the plurality of conductive members 28 as insert members.

[0035] The pump portion 40 is connected to the underside of the rotor 10. When the rotor 10 rotates about the central axis J, the pump portion 40 rotates about the central axis J. The pump portion 40 is made of resin. The pump portion 40 has a base portion 41, a shroud portion 42, and a plurality of blade portions 43. In this embodiment, the base portion 41 is connected to the lower end of the second rotor resin portion 14. The second rotor resin portion 14 and the base portion 41 are part of the same single member. The base portion 41 is formed at the same time as the second rotor resin portion 14 is formed by insert molding. The base portion 41 is annular and surrounds the central axis J. In this embodiment, the base portion 41 is approximately annular and its center coincides with the central axis J when viewed in the axial direction. The outer diameter of the base portion 41 is larger than the outer diameter of the second rotor resin portion 14 at its lower end.

[0036] The shroud portion 42 is disposed below the base portion 41 with a gap therebetween. When viewed in the axial direction, the shroud portion 42 has an annular shape whose center coincides with the central axis J. The shroud portion 42 is, for example, a separate body from the base portion 41. The plurality of blade portions 43 are located axially between the base portion 41 and the shroud portion 42. Lower ends of the plurality of blade portions 43 are connected to the shroud portion 42. The shroud portion 42 and the plurality of blade portions 43 are, for example, part of the same single member. Upper ends of the plurality of blade portions 43 contact the base portion 41.

[0037] The circuit board 95 extends in the radial direction. The plate surface of the circuit board 95 faces the axial direction. More specifically, the plate surface of the circuit board 95 is perpendicular to the axial direction. The circuit board 95 is, for example, a printed wiring board. In this embodiment, the circuit board 95 is provided with an inverter circuit that supplies power to the coil 23. The circuit board 95 is located above the stator 20a. The circuit board 95 is located above the stator resin main body 24s. The radial outer edge of the circuit board 95 is located radially inward from the outer peripheral surface of the stator resin main body 24s. The circuit board 95 is located above and spaced apart from the upper surface of the stator resin main body 24s.

[0038] The circuit board 95 is fixed to the stator assembly 20. In this embodiment, the circuit board 95 is fixed to a plurality of board support portions 27. The circuit board 95 is supported from below by the plurality of board support portions 27. The circuit board 95 has a plurality of holes 95a through which the plurality of board support portions 27 are respectively passed in the axial direction. The peripheral portions of the holes 95a on the lower surface of the circuit board 95 contact the upper end surface of the first portion 27a. This allows the circuit board 95 to be supported from below by the board support portions 27. The circuit board 95 has a hole 95b through which a second terminal portion 65b (described later) is passed in the axial direction, and a hole 95c through which a connection terminal portion 28b is passed in the axial direction. A plurality of electronic components 96 are attached to the circuit board 95.

[0039] As shown in FIG. 5, the housing 50 is tubular and open on the upper side. In this embodiment, the housing 50 is substantially cylindrical and centered on the central axis J. The stator assembly 20 is accommodated inside the housing 50. The housing 50 is made of resin. The housing 50 has a housing tubular portion 51 and a pump accommodating portion 52. The housing tubular portion 51 is tubular and open on the upper side. In this embodiment, the housing tubular portion 51 is substantially cylindrical and centered on the central axis J. As shown in FIG. 2, the housing tubular portion 51 is located radially outside the stator 20a. The housing tubular portion 51 surrounds the stator 20a from the radial outside.

[0040] 5, the cylindrical housing portion 51 has a first cylindrical portion 51a, a second cylindrical portion 51b, a third cylindrical portion 51c, and a fourth cylindrical portion 51d. The first cylindrical portion 51a, the second cylindrical portion 51b, the third cylindrical portion 51c, and the fourth cylindrical portion 51d are arranged in this order from bottom to top. The lower end of the first cylindrical portion 51a is the lower end of the cylindrical housing portion 51.

[0041] The second cylindrical portion 51b is located above the first cylindrical portion 51a. The lower end of the second cylindrical portion 51b is connected to the upper end of the first cylindrical portion 51a. The inner diameter of the second cylindrical portion 51b is larger than the inner diameter of the first cylindrical portion 51a. The axial dimension of the second cylindrical portion 51b is larger than the axial dimension of the first cylindrical portion 51a. A first step surface 51e facing upward is provided between the inner circumferential surfaces of the first cylindrical portion 51a and the second cylindrical portion 51b. The first step surface 51e is annular and surrounds the central axis J. In this embodiment, the first step surface 51e is annular in shape with its center coinciding with the central axis J when viewed in the axial direction.

[0042] The third cylindrical portion 51c is located above the second cylindrical portion 51b. The lower end of the third cylindrical portion 51c is connected to the upper end of the second cylindrical portion 51b. The inner diameter of the third cylindrical portion 51c is larger than the inner diameter of the second cylindrical portion 51b. The axial dimension of the third cylindrical portion 51c is smaller than the axial dimension of the first cylindrical portion 51a. A second step surface 51f facing upward is provided between the inner circumferential surfaces of the second cylindrical portion 51b and the third cylindrical portion 51c in the axial direction. The second step surface 51f is annular and surrounds the central axis J. In this embodiment, the second step surface 51f is annular and its center coincides with the central axis J when viewed in the axial direction. As shown in FIG. 4, the second step surface 51f is located below the upper surface of the stator resin main body 24s.

[0043] The fourth cylindrical portion 51d is located above the third cylindrical portion 51c. The lower end of the fourth cylindrical portion 51d is connected to the upper end of the third cylindrical portion 51c. The upper end of the fourth cylindrical portion 51d is the upper end of the housing cylindrical portion 51. The inner diameter of the fourth cylindrical portion 51d is larger than the inner diameter of the third cylindrical portion 51c. As shown in FIG. 5, the axial dimension of the fourth cylindrical portion 51d is larger than the axial dimension of the first cylindrical portion 51a and smaller than the axial dimension of the second cylindrical portion 51b. A third stepped surface 51g facing upward is provided between the inner circumferential surfaces of the third cylindrical portion 51c and the fourth cylindrical portion 51d. The third stepped surface 51g is provided on the inner circumferential surface of the housing cylindrical portion 51, is an annular stepped surface facing upward, and surrounds the central axis J. In the present embodiment, the third step surface 51g has an annular shape whose center coincides with the central axis J when viewed in the axial direction. As shown in Fig. 4, the third step surface 51g is located above the upper surface of the stator resin main body 24s. The third step surface 51g may be located at the same position in the axial direction as the upper surface of the stator resin main body 24s, or may be located below the upper surface of the stator resin main body 24s.

[0044] As shown in FIG. 2, at least a portion of the cylindrical housing portion 51 located above the stator 20a is embedded in the molded resin portion 70. As shown in FIG. 4, in this embodiment, an upper portion of the third cylindrical portion 51c and the fourth cylindrical portion 51d are embedded in the molded resin portion 70. The cylindrical housing portion 51 has a first through hole 51h penetrating the cylindrical housing portion 51 from its inner peripheral surface to its outer peripheral surface in the portion embedded in the molded resin portion 70. In this embodiment, the first through hole 51h is provided in the fourth cylindrical portion 51d. As shown in FIG. 5, the first through hole 51h extends in the circumferential direction. A plurality of the first through holes 51h are provided at intervals in the circumferential direction. In this embodiment, four first through holes 51h are provided. The inner surface of the first through hole 51h has a surface facing upward, a surface facing downward, a surface facing one circumferential side, and a surface facing the other circumferential side.

[0045] The cylindrical housing portion 51 has a through-hole 51i that penetrates the cylindrical housing portion 51 from the inner peripheral surface to the outer peripheral surface. The through-hole 51i is provided in the fourth cylindrical portion 51d. The through-hole 51i opens upward. The through-hole 51i is provided between a pair of adjacent first through-holes 51h that are spaced apart in the circumferential direction.

[0046] As shown in FIG. 2 , the stator assembly 20 is located radially inside the housing tubular portion 51. The first annular resin portion 24b is fitted radially inside the housing tubular portion 51. Therefore, the stator 20a can be positioned radially relative to the housing 50 via the stator resin portion 24. In this embodiment, the large diameter portion 24c of the first annular resin portion 24b is fitted radially inside the second tubular portion 51b of the housing tubular portion 51. In this embodiment, the first annular resin portion 24b is press-fitted radially inside the housing tubular portion 51 with the rib 26 in contact with the inner circumferential surface of the housing tubular portion 51. When the stator assembly 20 is fitted radially inside the first annular resin portion 24b, the rib 26 is elastically deformed, for example, in the radial direction. The rib 26 contacts the inner circumferential surface of the second tubular portion 51b.

[0047] The ribs 26 do not necessarily have to be provided on the stator resin portion 24, but may also be provided on the housing 50. For example, the ribs 26 may be provided on a protruding portion 55 of the housing 50, which will be described later. When the ribs 26 are provided on the protruding portion 55, the ribs 26 protrude radially inward from the radially inner surface of the protruding portion 55 and extend in the axial direction. When the ribs 26 are provided on the protruding portion 55, the ribs 26 come into contact with the radially outer surface of the recessed portion 24e of the stator resin portion 24 and are elastically deformed in the radial direction. This allows the stator assembly 20 to be press-fitted radially inside the cylindrical housing portion 51 when the stator assembly 20 is assembled to the cylindrical housing portion 51. When the ribs 26 are provided on the housing 50, the ribs 26 may be provided on the inner circumferential surface of the cylindrical housing portion 51 at a location circumferentially offset from a location where the protruding portion 55, which will be described later, is provided.

[0048] A first step surface 51e provided on the inner peripheral surface of the housing cylindrical portion 51 is in contact with a fourth step surface 24g provided on the outer peripheral surface of the stator resin main body portion 24s from above. This positions the stator resin portion 24 axially relative to the housing 50, and positions the stator 20a axially relative to the housing 50. The small diameter portion 24d of the first annular resin portion 24b is located radially inside the first cylindrical portion 51a. The outer peripheral surface of the small diameter portion 24d is located radially inside and spaced apart from the inner peripheral surface of the first cylindrical portion 51a. A radially outer end of the lower surface of the first annular resin portion 24b is located above an annular wall portion 52b (described later) of the pump accommodating portion 52, with a gap therebetween.

[0049] As shown in FIG. 4, the inner circumferential surface of the third cylindrical portion 51c of the housing tubular portion 51 is an inner circumferential surface portion 51k that is spaced radially outward from the outer circumferential surface of the first annular resin portion 24b. That is, the inner circumferential surface of the housing tubular portion 51 has the inner circumferential surface portion 51k. The inner circumferential surface portion 51k is located above the portion of the inner circumferential surface of the housing tubular portion 51 with which the first annular resin portion 24b is fitted, i.e., above the inner circumferential surface of the second cylindrical portion 51b. The inner circumferential surface portion 51k is located radially outward from the inner circumferential surface of the second cylindrical portion 51b. The inner circumferential surface portion 51k is located radially inward from the inner circumferential surface of the fourth cylindrical portion 51d. The inner circumferential surface portion 51k, the second step surface 51f, and the outer circumferential surface of the first annular resin portion 24b form an annular groove 51m that opens upward and surrounds the central axis J. The second step surface 51f is the bottom surface of the groove 51m.

[0050] As shown in FIG. 2, the pump accommodating portion 52 is located below the cylindrical housing portion 51. The pump accommodating portion 52 is connected to the lower end of the cylindrical housing portion 51. The axial dimension of the pump accommodating portion 52 is smaller than the axial dimension of the cylindrical housing portion 51. The pump accommodating portion 52 accommodates the pump portion 40 therein. The internal space of the pump accommodating portion 52 is connected to the internal space of the rotor accommodating portion 24r. The pump accommodating portion 52 has an annular bottom wall portion 52a that surrounds the central axis J and an annular wall portion 52b that protrudes upward from the radial outer edge of the bottom wall portion 52a. The bottom wall portion 52a is located below the pump portion 40. The radially outer end of the bottom wall portion 52a is located radially outward of the pump portion 40. The annular wall portion 52b is annular, surrounds the central axis J, and opens upward. The inner diameter of the annular wall portion 52b is smaller than the inner diameter of the cylindrical housing portion 51. The radially outer edge portion at the upper end of the annular wall portion 52b is connected to the lower end of the cylindrical housing portion 51. The annular wall portion 52b is located radially outside the pump portion 40. The annular wall portion 52b surrounds the pump portion 40.

[0051] The pump accommodating portion 52 has a flow path portion 52c. The flow path portion 52c is located radially outside the pump portion 40. The flow path portion 52c is provided radially between the pump portion 40 and the annular wall portion 52b. Although not shown in the figure, the flow path portion 52c extends in the circumferential direction.

[0052] The housing 50 has an intake port 53. The intake port 53 protrudes downward from the radial inner edge of the bottom wall 52a. In this embodiment, the intake port 53 has a substantially cylindrical shape centered on the central axis J. The intake port 53 opens downward. The internal space of the intake port 53 is connected to the internal space of the pump accommodating portion 52.

[0053] When the rotor 10 rotates and the pump section 40 rotates, water is drawn into the pump housing section 52 through the suction port section 53. At least a portion of the water drawn into the pump housing section 52 is drawn into the interior of the pump section 40 from the radially inner side of the shroud section 42. The water drawn into the pump section 40 is discharged radially outward from the pump section 40, flows circumferentially along the flow path section 52c, and is discharged to the outside of the electric pump 100 through a discharge port section (not shown). Note that a portion of the water drawn into the suction port section 53 also flows into the rotor housing section 24r, for example.

[0054] The housing 50 has a rotor support portion 57 that supports the rotor 10 from below. The rotor support portion 57 has a support main body portion 57a ​​and multiple leg portions 57b. The support main body portion 57a ​​supports the rotor 10 from below via a washer 32. The fixed shaft 30 is passed axially through the inside of the washer 32. The washer 32 contacts the upper end of the support main body portion 57a ​​and the lower end of the bearing portion 15. The multiple leg portions 57b extend upward from the inner circumferential surface of the suction port portion 53. The upper ends of the multiple leg portions 57b are connected to the support main body portion 57a.

[0055] As shown in FIG. 5, the housing 50 has a first annular protrusion 54. The first annular protrusion 54 protrudes upward from the third step surface 51g. The first annular protrusion 54 has an annular shape surrounding the central axis J. In this embodiment, the first annular protrusion 54 has a circular shape whose center coincides with the central axis J when viewed in the axial direction. As shown in FIG. 4, in a cross section perpendicular to the circumferential direction, the first annular protrusion 54 has a generally triangular shape that is convex upward. The first annular protrusion 54 is embedded in the molded resin portion 70. An upper end of the first annular protrusion 54 is located below the first through-hole 51h. The first annular protrusion 54 is located above the second annular protrusion 25.

[0056] As shown in FIG. 5, the housing 50 has a protrusion 55 that protrudes radially inward from the inner circumferential surface of the housing cylindrical portion 51. In this embodiment, the protrusion 55 protrudes radially inward from the inner circumferential surface of the second cylindrical portion 51b. The protrusion 55 extends in the axial direction. A lower end of the protrusion 55 is connected to the first step surface 51e. An upper end of the protrusion 55 is located lower than an upper end of the inner circumferential surface of the second cylindrical portion 51b. A radially inner surface of the protrusion 55 is located radially outward from the inner circumferential surface of the first cylindrical portion 51a. A plurality of protrusions 55 are provided at intervals in the circumferential direction. For example, three protrusions 55 are provided. As shown in FIG. 2, each protrusion 55 is fitted into a corresponding recess 24e. This positions the stator assembly 20 circumferentially relative to the housing 50. As described above, when the rib 26 is provided on the protrusion 55, the rib 26 is brought into contact with the radially outer surface of the recess 24e, and the stator assembly 20 is pressed into the radially inner side of the housing cylindrical portion 51, and the protrusion 55 is fitted into the recess 24e, thereby positioning the stator assembly 20 circumferentially relative to the housing 50.

[0057] 5, the housing 50 has a plurality of fixing portions 56 that protrude radially outward from the housing cylindrical portion 51. The fixing portions 56 are arranged at intervals in the circumferential direction. The fixing portions 56 are portions that are fixed to the equipment to which the electric pump 100 is attached. Each fixing portion 56 is fixed to the equipment to which the electric pump 100 is attached, for example, by a bolt that passes through each fixing portion 56 in the axial direction.

[0058] As shown in FIG. 2, the cover assembly 60 is located above the stator assembly 20. The cover assembly 60 has a cover 61, a connector portion 62, and a connector terminal 65. The cover 61 and the connector portion 62 are made of resin. In this embodiment, the cover 61 and the connector portion 62 are part of the same single member. The cover 61 and the connector portion 62 are made, for example, by insert molding using the connector terminal 65 as an insert member.

[0059] The cover 61 covers the circuit board 95 from above. The cover 61 is located radially inside the cylindrical housing portion 51. The cover 61 has a lid portion 61a and a cylindrical cover portion 61b. The lid portion 61a is located above the circuit board 95. The lid portion 61a covers the circuit board 95 from above. The lid portion 61a extends in the radial direction. In this embodiment, the lid portion 61a is plate-shaped with its plate surface facing the axial direction. The lid portion 61a sandwiches the circuit board 95 in the axial direction between the lid portion 61a and the stator resin main body 24s. In other words, the circuit board 95 is located axially between the stator resin main body 24s and the lid portion 61a. The lid portion 61a is provided above and spaced apart from the circuit board 95. As shown in FIG. 6, in this embodiment, the lid portion 61a has a circular shape whose center coincides with the central axis J when viewed in the axial direction. 4, the upper surface of the lid portion 61a is located at the same axial position as the upper end portion of the cylindrical housing portion 51. In other words, the upper end portion of the cylindrical housing portion 51 is located at the same axial position as the upper surface of the lid portion 61a.

[0060] The cover tubular portion 61b protrudes downward from the lid portion 61a. In this embodiment, the cover tubular portion 61b protrudes downward from the radial outer edge of the lid portion 61a. The cover tubular portion 61b is tubular and opens downward. In this embodiment, the cover tubular portion 61b is cylindrical and centered on the central axis J. The cover tubular portion 61b is located radially outside the circuit board 95. The cover tubular portion 61b surrounds the circuit board 95. At least a portion of the cover tubular portion 61b is located radially inside the cylindrical housing portion 51. In this embodiment, the entire cover tubular portion 61b is located radially inside the cylindrical housing portion 51. The cover tubular portion 61b is located radially inside the third cylindrical portion 51c and the fourth cylindrical portion 51d. The outer peripheral surface of the cover tubular portion 61b is spaced radially inward from the inner peripheral surface of the cylindrical housing portion 51.

[0061] The lower end of the cover cylindrical portion 61b is fitted into the annular groove 24f. This allows the cover 61 to be positioned radially relative to the stator resin main body portion 24s. In this embodiment, the lower end of the cover cylindrical portion 61b is clearance-fitted into the annular groove 24f. The lower end of the cover cylindrical portion 61b may be press-fit into the annular groove 24f. The lower end of the cover cylindrical portion 61b contacts the stator resin main body portion 24s from above. In this embodiment, the lower end of the cover cylindrical portion 61b contacts the bottom surface of the inner surface of the annular groove 24f, which is located on the lower side.

[0062] The lower opening of the cover 61, i.e., the lower opening of the cover cylindrical portion 61b, is closed by the stator resin main body 24s. The cover 61 and the stator resin main body 24s form a board accommodating portion 90 that accommodates a circuit board 95 therein.

[0063] The cover 61 has a third annular protrusion 63 protruding upward from the upper surface of the lid portion 61a. In this embodiment, the third annular protrusion 63 is provided on a radially outer portion of the upper surface of the lid portion 61a. As shown in FIG. 6 , the third annular protrusion 63 is annular and surrounds the central axis J. In this embodiment, the third annular protrusion 63 is annular and has a center that coincides with the central axis J when viewed in the axial direction. In this embodiment, a plurality of third annular protrusions 63 are provided at intervals in the radial direction. In this embodiment, two third annular protrusions 63 are provided: a third annular protrusion 63a and a third annular protrusion 63b. The outer diameter of the third annular protrusion 63b is larger than the outer diameter of the third annular protrusion 63a. The third annular protrusion 63b is disposed radially outward from the third annular protrusion 63a at a distance. The third annular protrusion 63b surrounds the third annular protrusion 63a. 4, the third annular protrusion 63 has a generally triangular shape that is convex upward in a cross section perpendicular to the circumferential direction. The third annular protrusion 63 is embedded in the molded resin portion .

[0064] 7, when the molded resin portion 70 is formed, the tip portion 63c of the third annular protrusion 63 is melted by the molten resin poured into the mold and becomes mixed with the resin that constitutes the molded resin portion 70. The tip portion 63c melts and becomes irregularly shaped, and the boundary between the tip portion 63c and the molded resin portion 70 becomes irregular and complex. Although not shown, the tip portions of the first annular protrusion 54 and the second annular protrusion 25 are also melted and mixed with the resin that constitutes the molded resin portion 70, similar to the tip portion 63c of the third annular protrusion 63.

[0065] As shown in FIG. 6, the connector portion 62 protrudes radially outward from the cover 61. More specifically, the connector portion 62 protrudes radially outward from the outer peripheral surface of the cover cylindrical portion 61b. The connector portion 62 has a connector base 62a and a connector cylindrical portion 62b. The connector base 62a protrudes radially outward from the cover 61. The connector base 62a has a substantially rectangular parallelepiped shape. As shown in FIG. 2, the connector base 62a is passed radially through the through portion 51i. A radially outer end of the connector base 62a is located outside the housing cylindrical portion 51.

[0066] The connector tubular portion 62b is connected to the radially outer end of the connector base portion 62a. The connector tubular portion 62b is cylindrical and opens radially outward. As shown in FIG. 6, the connector tubular portion 62b is substantially rectangular. The axial dimension of the connector tubular portion 62b is larger than the axial dimension of the connector base portion 62a. The circumferential dimension of the connector tubular portion 62b is larger than the circumferential dimension of the connector base portion 62a.

[0067] The connector terminal 65 is a metal member. As shown in FIG. 2, a portion of the connector terminal 65 is embedded in the connector portion 62. A portion of the connector terminal 65 is embedded in the connector base 62a and the radially inner bottom of the connector tubular portion 62b. In this embodiment, another portion of the connector terminal 65 is embedded in the lid portion 61a. The connector terminal 65 has a first terminal portion 65a and a second terminal portion 65b. The first terminal portion 65a protrudes radially outward from the radially inner bottom of the connector tubular portion 62b. The first terminal portion 65a is exposed to the internal space of the connector tubular portion 62b. The second terminal portion 65b protrudes downward from the lower surface of the lid portion 61a. The second terminal portion 65b is press-fit into a hole 95b provided in the circuit board 95 and is electrically connected to the circuit board 95. The second terminal portion 65b is, for example, a press-fit terminal. The radially outer end of the first terminal portion 65a is one end of the connector terminal 65. The lower end of the second terminal portion 65b is the other end of the connector terminal 65. In this embodiment, the entire connector terminal 65 except for the first terminal portion 65a and the second terminal portion 65b is embedded in the connector portion 62.

[0068] An external power supply (not shown) is connected to the connector portion 62. The external power supply is electrically connected to a first terminal portion 65a exposed inside the connector cylindrical portion 62b. Power from the external power supply is supplied to the circuit board 95 via the connector terminal 65. A portion of the power supplied to the circuit board 95 is supplied to the coil 23 via the conductive member 28.

[0069] As shown in FIG. 6 , the connector portion 62 has a fourth annular protrusion 64. The fourth annular protrusion 64 is provided on the outer surface of the connector base 62a. The fourth annular protrusion 64 is annular and surrounds the connector base 62a around an axis extending in the radial direction in which the connector portion 62 protrudes. In this embodiment, the fourth annular protrusion 64 has a square frame shape when viewed in the radial direction in which the connector portion 62 protrudes. In this embodiment, a plurality of fourth annular protrusions 64 are provided at intervals in the radial direction in which the connector portion 62 protrudes. In this embodiment, two fourth annular protrusions 64, a fourth annular protrusion 64a and a fourth annular protrusion 64b, are provided. The fourth annular protrusion 64b is provided radially outward of the fourth annular protrusion 64a and spaced apart from each other. As shown in FIG. 2 , in a cross section perpendicular to the direction in which the fourth annular protrusion 64 extends, the fourth annular protrusion 64 has a generally triangular shape that is convex in a direction away from the outer surface of the connector base 62a. The fourth annular protrusion 64 is embedded in the molded resin portion 70. Although not shown in the drawings, the tip portion of the fourth annular protrusion 64 is also melted and mixed with the resin that constitutes the molded resin portion 70, similar to the tip portion 63c of the third annular protrusion 63 shown in FIG.

[0070] The molded resin portion 70 is made of resin. For example, the molded resin portion 70 is produced by insert molding using an assembly 100b (see FIG. 11 ), which is an assembly of the electric pump 100 except for the molded resin portion 70, as an insert member. As shown in FIG. 1 , the molded resin portion 70 is located at the upper end of the electric pump 100. In this embodiment, the molded resin portion 70 is annular and surrounds the central axis J. More specifically, the molded resin portion 70 is substantially annular, the center of which coincides with the central axis J, as viewed in the axial direction. As shown in FIG. 2 , the molded resin portion 70 contacts at least a portion of the housing 50 and at least a portion of the cover 61, thereby connecting the housing 50 and the cover 61. Therefore, a worker or the like who manufactures the electric pump 100 can connect the housing 50 and the cover 61 by molding the molded resin portion 70 with resin using a mold. This reduces the number of steps and time required to assemble the electric pump 100 compared to, for example, fixing the cover 61 and the pump housing portion 52 separately to the stator resin portion 24 by welding or the like. Therefore, the number of steps and time required to manufacture the electric pump 100 can be reduced.

[0071] In this specification, the term "workers, etc." includes workers who perform each task and assembly equipment, etc. Each task may be performed by a worker alone, by an assembly equipment alone, or by a worker and an assembly equipment together.

[0072] As shown in FIG. 1 , the molded resin part 70 has a resin lid part 71 and a second annular resin part 72. The resin lid part 71 is a part that contacts the upper surface of the lid part 61a. The resin lid part 71 is annular and surrounds the central axis J. In this embodiment, the resin lid part 71 is substantially annular in shape, the center of which coincides with the central axis J when viewed in the axial direction. In this embodiment, the resin lid part 71 contacts a radially outer portion of the upper surface of the lid part 61a. The upper surface of the resin lid part 71 is the upper surface of the molded resin part 70.

[0073] The second annular resin portion 72 protrudes downward from the radial outer edge of the resin lid portion 71. The second annular resin portion 72 has an annular shape surrounding the central axis J. In the present embodiment, the second annular resin portion 72 has a substantially circular annular shape whose center coincides with the central axis J when viewed in the axial direction. As shown in FIG. 2 , the second annular resin portion 72 is located radially outside the tubular cover portion 61b. The second annular resin portion 72 surrounds the tubular cover portion 61b. In the present embodiment, the lower end of the second annular resin portion 72 is located above the upper end of the stator 20a. The outer peripheral surface of the second annular resin portion 72 is located radially outside the outer peripheral surface of the fourth tubular portion 51d. The axial dimension of the second annular resin portion 72 is equal to or less than half the axial dimension of the tubular housing portion 51.

[0074] The second annular resin portion 72 fills the radial gap between the housing tubular portion 51 and the cover tubular portion 61b around the central axis J. In other words, the molded resin portion 70 fills the gap between the housing 50 and the cover 61 around the central axis J. Therefore, by forming the molded resin portion 70, the housing 50 and the cover 61 can be connected to each other and the gap between the housing 50 and the cover 61 can be filled. Therefore, the molded resin portion 70 can prevent foreign matter such as liquid from entering the gap between the housing 50 and the cover 61 from outside the electric pump 100. Furthermore, because the molded resin portion 70 fills the gap between the housing 50 and the cover 61 around the central axis J, the housing 50 and the cover 61 can be more firmly connected to each other via the molded resin portion 70.

[0075] As shown in FIG. 4 , the second annular resin portion 72 contacts the entire outer circumferential surface of the cover tubular portion 61b except for the portion positioned within the annular groove 24f. The second annular resin portion 72 has a portion positioned radially between the outer circumferential surface of the cover tubular portion 61b and the inner circumferential surface of the housing tubular portion 51, a portion positioned radially outside the housing tubular portion 51, and a portion positioned inside the first through-hole 51h. The lower end of the portion of the second annular resin portion 72 positioned radially outside the housing tubular portion 51 is positioned below the upper surface of the stator resin main body 24s and above the second step surface 51f. Note that the lower end of the portion of the second annular resin portion 72 positioned radially outside the housing tubular portion 51 may be located at the same axial position as the upper surface of the stator resin main body 24s or may be located above the upper surface of the stator resin main body 24s.

[0076] 2, the upper end of the portion of the second annular resin portion 72 located radially between the outer peripheral surface of the tubular cover portion 61b and the inner peripheral surface of the tubular housing portion 51 is located above the first terminal portion 65a. The lower end of the portion of the second annular resin portion 72 located radially between the outer peripheral surface of the tubular cover portion 61b and the inner peripheral surface of the tubular housing portion 51 is located below the first terminal portion 65a. In other words, the portion of the molded resin portion 70 located radially between the outer peripheral surface of the tubular cover portion 61b and the inner peripheral surface of the tubular housing portion 51 has a portion that is located at the same position as the first terminal portion 65a in the axial direction. This prevents the housing 50 and the cover 61 from becoming disconnected even if a radial load is applied to the connector portion 62 when attaching or detaching an external power source to or from the connector portion 62.

[0077] As shown in FIG. 4 , the second annular resin portion 72 contacts at least a portion of the tubular housing portion 51. The second annular resin portion 72 contacts at least a portion of the tubular housing portion 51 that is located above the stator 20a. That is, at least a portion of the tubular housing portion 51 that is located above the stator 20a contacts the molded resin portion 70. The molded resin portion 70 connects the tubular housing portion 51 to the cover 61. The tubular housing portion 51 surrounds the stator 20a from the radial outside and is therefore positioned closer to the cover 61 in the axial direction than the pump accommodating portion 52. Therefore, connecting the tubular housing portion 51 to the cover 61 with the molded resin portion 70 can reduce the axial dimension of the molded resin portion 70 compared to connecting the pump accommodating portion 52 to the cover 61 with the molded resin portion 70. This reduces the amount of resin required to mold the molded resin portion 70. Therefore, the amount of molten resin poured into the mold when molding the molded resin portion 70 can be reduced, and the amount of heat transferred from the molten resin to the assembly 100b in the mold can be reduced. As a result, the temperature rise of the circuit board 95 and the rotor 10 can be suppressed when molding the molded resin portion 70. Therefore, damage to the circuit board 95 due to heat and demagnetization of the magnets 12 in the rotor 10 due to heat can be suppressed when molding the molded resin portion 70. Furthermore, by reducing the axial dimension of the molded resin portion 70, sink marks are less likely to occur when molding the molded resin portion 70. Furthermore, by reducing the axial dimension of the molded resin portion 70, the electric pump 100 can be more easily miniaturized.

[0078] At least a portion of the cylindrical housing portion 51 located above the stator 20a is embedded in the second annular resin portion 72. That is, at least a portion of the cylindrical housing portion 51 located above the stator 20a is embedded in the molded resin portion 70. This allows the housing 50 and the molded resin portion 70 to be more firmly fixed together. The cylindrical housing portion 51 has a first through hole 51h that penetrates the cylindrical housing portion 51 from its inner circumferential surface to its outer circumferential surface in the portion embedded in the molded resin portion 70. This allows a portion of the molded resin portion 70 to be positioned within the first through hole 51h, allowing the molded resin portion 70 to come into contact with the inner surface of the first through hole 51h. This increases the contact area between the molded resin portion 70 and the housing 50, thereby allowing the housing 50 and the molded resin portion 70 to be more firmly fixed together. Furthermore, because the molded resin part 70 is caught on an upper surface of the inner surface of the first through hole 51h, even if the molded resin part 70 is subjected to an upward force, it is possible to prevent the molded resin part 70 from coming off the housing 50. Furthermore, because the molded resin part 70 is caught on a surface of the inner surface of the first through hole 51h that faces in the circumferential direction, it is possible to prevent the molded resin part 70 from rotating (spinning freely) relative to the housing 50, even if the molded resin part 70 is subjected to a circumferential force.

[0079] 2, the first through-hole 51h has a portion that is provided at the same position as the first terminal portion 65a in the axial direction. This makes it possible to further prevent the connection between the housing 50 and the cover 61 from coming loose even if a radial load is applied to the connector portion 62 when connecting or disconnecting an external power supply to or from the connector portion 62.

[0080] In the present embodiment, the second annular resin portion 72 connects the tubular housing portion 51 and the tubular cover portion 61b, at least a portion of which is located radially inside the tubular housing portion 51. In other words, the molded resin portion 70 connects the tubular housing portion 51 and the tubular cover portion 61b. Because the tubular housing portion 51 and the tubular cover portion 61b, which are at least partially overlapped in the radial direction, can be connected by the molded resin portion 70, the molded resin portion 70 can more firmly connect the housing 50 and the cover 61.

[0081] In the present embodiment, the second annular resin portion 72 contacts almost the entire surface of a portion of the housing cylindrical portion 51 that is positioned above the stator 20a. The second annular resin portion 72 contacts the inner circumferential surface of the upper portion of the third cylindrical portion 51c, the outer circumferential surface of the upper portion of the third cylindrical portion 51c, the inner circumferential surface of the fourth cylindrical portion 51d, the outer circumferential surface of the fourth cylindrical portion 51d, the third step surface 51g, the inner surface of the first through hole 51h, and the upper end surface of the housing cylindrical portion 51.

[0082] As shown in FIG. 4 , in this embodiment, the molded resin portion 70 contacts the outer peripheral surface of the tubular cover portion 61b, the inner peripheral surface of the tubular housing portion 51, the outer peripheral surface of the tubular housing portion 51, the upper surface of the lid portion 61a, and the upper end surface of the tubular housing portion 51 via the resin lid portion 71 and the second annular resin portion 72. This increases the contact area between the molded resin portion 70 and the housing 50 and the contact area between the molded resin portion 70 and the cover 61. Furthermore, the molded resin portion 70 can contact both the radial and axial surfaces of the housing 50 and the cover 61. This allows the housing 50 and the cover 61 to be more firmly connected via the molded resin portion 70.

[0083] In this embodiment, the upper end of the tubular housing portion 51 is located at the same axial position as the upper surface of the lid portion 61a. Therefore, when resin is poured into a mold from above the lid portion 61a to form the molded resin portion 70, the poured resin can more easily flow along the upper side of the tubular housing portion 51 than when the upper end of the tubular housing portion 51 is located above the upper surface of the lid portion 61a. This makes it easier to form the molded resin portion 70 and to embed a portion of the tubular housing portion 51 in the molded resin portion 70. Note that the upper end of the tubular housing portion 51 may be located below the surface of the other axial side of the lid portion 61a. Even in this case, when resin is poured into a mold from above the lid portion 61a to form the molded resin portion 70, the poured resin can more easily flow along the upper side of the tubular housing portion 51.

[0084] The first annular protrusion 54 provided on the housing 50 is embedded in the molded resin portion 70. In this embodiment, the first annular protrusion 54 is embedded in the second annular resin portion 72. When the molded resin portion 70 is molded, a portion of the first annular protrusion 54 is melted by the molten resin poured into the mold and becomes mixed with the resin that constitutes the molded resin portion 70. Specifically, as described above, the tip of the first annular protrusion 54 melts and becomes irregularly shaped, like the tip portion 63c of the third annular protrusion 63 shown in FIG. 7, and becomes mixed with the resin that constitutes the molded resin portion 70. Therefore, the boundary between the first annular protrusion 54 and the molded resin portion 70 has a complex shape, which makes it possible to prevent liquids from passing through the boundary between the first annular protrusion 54 and the molded resin portion 70. As a result, even if liquid seeps into the boundary between the second annular resin portion 72 and the housing 50, for example, the liquid can be blocked at the boundary between the first annular protrusion 54 and the molded resin portion 70. Therefore, by providing the housing 50 with the first annular protrusion 54 embedded in the molded resin portion 70, the gap between the housing 50 and the molded resin portion 70 can be suitably sealed. Specifically, in this embodiment, even if water flowing through the flow path portion 52c seeps into the boundary between the stator resin portion 24 and the tubular housing portion 51, the water can be blocked at the boundary between the first annular protrusion 54 and the second annular resin portion 72. As a result, the water can be prevented from flowing into the boundary between the outer circumferential surface of the tubular housing portion 51 and the second annular resin portion 72, and the water can be prevented from leaking outside the electric pump 100 from the boundary between the lower end of the second annular resin portion 72 and the outer circumferential surface of the tubular housing portion 51.

[0085] As shown in FIG. 4 , in this embodiment, molded resin portion 70 contacts at least a portion of stator resin portion 24 and connects housing 50, cover 61, and stator resin portion 24. Therefore, by molding molded resin portion 70, stator resin portion 24 can be connected to housing 50 and cover 61. This allows workers to fix stator resin portion 24, in which at least a portion of stator 20a is embedded, by simply molding molded resin portion 70, without having to perform a separate operation to fix stator resin portion 24. This reduces the number of steps and time required to manufacture electric pump 100.

[0086] In this embodiment, the lower end of the cover tubular portion 61b contacts the stator resin main body 24s from above. Therefore, when molding the molded resin portion 70, it is possible to prevent molten resin from penetrating into the cover tubular portion 61b between the lower end of the cover tubular portion 61b and the stator resin main body 24s. This further prevents heat from being applied to the circuit board 95 by the molten resin when molding the molded resin portion 70, thereby further preventing the temperature of the circuit board 95 from increasing. This further prevents damage to the circuit board 95 due to heat. Furthermore, when molding the molded resin portion 70, molten resin is poured into the mold from above the cover 61, so that the molten resin presses the lower end of the cover tubular portion 61b against the stator resin main body 24s from above. This further prevents molten resin from penetrating into the cover tubular portion 61b between the lower end of the cover tubular portion 61b and the stator resin main body 24s.

[0087] In this embodiment, the lower end of the cover tubular portion 61b is fitted into the annular groove 24f. This makes it easy to increase the contact area between the lower end of the cover tubular portion 61b and the stator resin main body portion 24s. As a result, the annular groove 24f can more effectively prevent resin from passing between the cover tubular portion 61b and the stator resin main body portion 24s when molding the molded resin portion 70. Therefore, when molding the molded resin portion 70, it is more effectively prevented molten resin from entering the inside of the cover tubular portion 61b from between the lower end of the cover tubular portion 61b and the stator resin main body portion 24s. This can more effectively prevent damage to the circuit board 95 due to heat.

[0088] In this embodiment, the molded resin portion 70 has a filling portion 73 as a portion filled radially between the inner peripheral surface portion 51k and the outer peripheral surface of the first annular resin portion 24b. Therefore, the filling portion 73 can press the stator resin portion 24 from the radial outside. Therefore, the molded resin portion 70 can more firmly fix the stator resin portion 24. The filling portion 73 is filled in the groove 51m. The filling portion 73 is annular and surrounds the central axis J. The filling portion 73 contacts the inner peripheral surface portion 51k and the outer peripheral surface of the first annular resin portion 24b.

[0089] The molded resin portion 70 contacts a portion of the second annular resin portion 72 on the upper surface of the stator resin main body 24s that is located radially outward of the cover cylindrical portion 61b. The molded resin portion 70 contacts a portion of the filling portion 73 that includes the upper end of the outer circumferential surface of the large-diameter portion 24c of the stator resin main body 24s. That is, the molded resin portion 70 contacts the upper surface of the stator resin main body 24s and the radially outer surface of the stator resin main body 24s. This increases the contact area between the molded resin portion 70 and the stator resin portion 24. This allows the stator resin portion 24, the housing 50, and the cover 61 to be more firmly connected via the molded resin portion 70.

[0090] The second annular protrusion 25 provided on the stator resin portion 24 is embedded in the molded resin portion 70. In this embodiment, the second annular protrusion 25 is embedded in the second annular resin portion 72. When the molded resin portion 70 is formed, a portion of the second annular protrusion 25 is melted by the molten resin poured into the mold and becomes mixed with the resin constituting the molded resin portion 70. Specifically, as described above, the tip portion of the second annular protrusion 25 melts and becomes irregularly shaped like the tip portion 63c of the third annular protrusion 63 shown in FIG. 7 and becomes mixed with the resin constituting the molded resin portion 70. Therefore, the boundary between the second annular protrusion 25 and the molded resin portion 70 has a complex shape, which makes it possible to prevent liquids from passing through the boundary between the second annular protrusion 25 and the molded resin portion 70. As a result, even if liquid seeps into the boundary between the second annular resin portion 72 and the stator resin portion 24, for example, the liquid can be blocked at the boundary between the second annular protrusion 25 and the molded resin portion 70. Therefore, by providing the stator resin portion 24 with the second annular protrusion 25 embedded in the molded resin portion 70, the gap between the stator resin portion 24 and the molded resin portion 70 can be suitably sealed. Specifically, in this embodiment, even if water flowing through the flow path portion 52c seeps into the boundary between the stator resin portion 24 and the tubular housing portion 51, the water can be blocked at the boundary between the second annular protrusion 25 and the second annular resin portion 72. As a result, the water can be prevented from flowing into the boundary between the tubular cover portion 61b and the second annular resin portion 72, and the water can be prevented from entering the board accommodating portion 90 from the boundary between the tubular cover portion 61b and the second annular resin portion 72.

[0091] As shown in FIG. 7 , the third annular protrusion 63 provided on the cover 61 is embedded in the molded resin portion 70. In this embodiment, the third annular protrusion 63 is embedded in the resin lid portion 71. When the molded resin portion 70 is molded, a portion of the third annular protrusion 63 melts due to the molten resin poured into the mold and becomes mixed with the resin constituting the molded resin portion 70. Specifically, as described above, the tip portion 63c of the third annular protrusion 63 melts and becomes irregularly shaped, becoming mixed with the resin constituting the molded resin portion 70. This results in a complex shape at the boundary between the third annular protrusion 63 and the molded resin portion 70, which can prevent liquids from passing through the boundary between the third annular protrusion 63 and the molded resin portion 70. As a result, even if liquid penetrates the boundary between the resin lid portion 71 and the lid portion 61a, the liquid can be blocked at the boundary between the third annular protrusion 63 and the resin lid portion 71 of the molded resin portion 70. Therefore, by providing the third annular protrusion 63 embedded in the molded resin portion 70 on the upper surface of the lid portion 61a, the gap between the resin lid portion 71 and the lid portion 61a can be suitably sealed. Specifically, in this embodiment, even if liquid seeps into the boundary between the radial inner edge of the resin lid portion 71 and the lid portion 61a from outside the electric pump 100, the liquid can be blocked at the boundary between the third annular protrusion 63 and the resin lid portion 71. This prevents the liquid from flowing to the boundary between the outer circumferential surface of the cover tubular portion 61b and the second annular resin portion 72, and prevents the liquid from entering the substrate accommodating portion 90 from the boundary between the cover tubular portion 61b and the inner surface of the annular groove 24f.

[0092] In this embodiment, a plurality of third annular protrusions 63 are provided at intervals in the radial direction. Therefore, even if liquid passes through the boundary between one third annular protrusion 63 and the molded resin portion 70, the liquid can be blocked by the boundary between the other third annular protrusions 63 and the molded resin portion 70. This further improves the sealing performance between the resin lid portion 71 and the lid portion 61a.

[0093] As shown in FIG. 1 , gate marks 71a are provided on the upper surface of the molded resin portion 70. In this embodiment, the gate marks 71a are provided on the radially inner edge of the upper surface of the resin lid portion 71. A plurality of gate marks 71a are provided at intervals in the circumferential direction. The number of gate marks 71a is not particularly limited as long as it is one or more. The gate marks 71a are marks created by providing a gate through which resin is poured into a mold when molding the molded resin portion 70. For example, the gate marks 71a protrude slightly upward from the upper surface of the resin lid portion 71. For example, the gate marks 71a have a circular shape when viewed in the axial direction. Because the gate marks 71a are provided on the upper surface of the molded resin portion 70, resin can be poured from above when molding the molded resin portion 70, and the resin can press the cover 61 against the stator resin main body portion 24s. This makes it possible to suitably prevent resin from entering the substrate accommodating portion 90 when molding the molded resin portion 70, as described above.

[0094] As shown in FIG. 2 , the gate mark 71a is located radially inward of the third annular protrusion 63. Therefore, when molding the molded resin portion 70, resin can easily flow from the gate in one direction from the radially inner side to the radially outer side, making it easier to mold the molded resin portion 70. Furthermore, when molding the molded resin portion 70, resin can easily flow from a position close to the third annular protrusion 63, making it easier for relatively hot resin to come into contact with the third annular protrusion 63. This makes it easier for the molten resin to melt a portion of the third annular protrusion 63. Therefore, the third annular protrusion 63 can easily seal the gap between the cover 61 and the molded resin portion 70. Furthermore, resin that passes radially outward through the third annular protrusion 63 can flow radially between the housing tubular portion 51 and the cover tubular portion 61b. This allows molten resin poured into the mold from the gate to relatively quickly come into contact with the first annular protrusion 54 provided on the third stepped surface 51g provided on the inner circumferential surface of the housing tubular portion 51 and the second annular protrusion 25 provided on a portion of the upper surface of the stator resin main body 24s that is positioned radially outward from the cover tubular portion 61b. This allows relatively high-temperature resin to easily come into contact with the first annular protrusion 54 and the second annular protrusion 25, making it easier for the molten resin to melt a portion of the first annular protrusion 54 and a portion of the second annular protrusion 25. This allows the first annular protrusion 54 to easily seal the gap between the housing tubular portion 51 and the molded resin portion 70, and the second annular protrusion 25 to easily seal the gap between the stator resin main body 24s and the molded resin portion 70.

[0095] As shown in FIG. 2 , in this embodiment, the fourth annular protrusion 64 provided on the connector portion 62 is embedded in the molded resin portion 70. In this embodiment, the fourth annular protrusion 64 is embedded in the second annular resin portion 72. When the molded resin portion 70 is molded, a portion of the fourth annular protrusion 64 is melted by the molten resin poured into the mold and becomes mixed with the resin constituting the molded resin portion 70. Specifically, as described above, the tip portion of the fourth annular protrusion 64 melts and becomes irregularly shaped, like the tip portion 63c of the third annular protrusion 63 shown in FIG. 7 , and becomes mixed with the resin constituting the molded resin portion 70. Therefore, the boundary between the fourth annular protrusion 64 and the molded resin portion 70 has a complex shape, which makes it possible to prevent liquids from passing through the boundary between the fourth annular protrusion 64 and the molded resin portion 70. As a result, even if liquid seeps into the boundary between the molded resin portion 70 and the connector portion 62, for example, the liquid can be blocked at the boundary between the fourth annular protrusion 64 and the molded resin portion 70. Therefore, by providing the connector portion 62 with the fourth annular protrusion 64 embedded in the molded resin portion 70, the gap between the molded resin portion 70 and the connector portion 62 can be suitably sealed. Specifically, in this embodiment, even if liquid seeps into the boundary between the connector portion 62 and the molded resin portion 70 from outside the electric pump 100, the liquid can be blocked at the boundary between the fourth annular protrusion 64 and the molded resin portion 70. As a result, the liquid can be prevented from flowing to the boundary between the outer circumferential surface of the cover tubular portion 61b and the second annular resin portion 72, and the liquid can be prevented from entering the board accommodating portion 90 from the boundary between the cover tubular portion 61b and the inner surface of the annular groove 24f.

[0096] 1, the molded resin portion 70 has a protruding resin portion 74. The protruding resin portion 74 protrudes radially outward from the outer peripheral surface of the second annular resin portion 72, in the direction in which the connector portion 62 protrudes. As shown in FIG. 2, a portion of the connector base portion 62a that is positioned radially outward from the tubular housing portion 51 is embedded in the protruding resin portion 74.

[0097] Portions of the housing 50, the cover 61, and the stator resin portion 24 that are in contact with the molded resin portion 70 are, for example, welded to the molded resin portion 70. Portions of the housing 50, the cover 61, and the stator resin portion 24 that are in contact with the molded resin portion 70 may be in tight contact with the molded resin portion 70.

[0098] The resins constituting the housing 50, the stator resin portion 24, the cover 61, and the connector portion 62 are resins with a relatively low heat of fusion (melting energy) [J / g]. The heat of fusion of the resins constituting the housing 50, the stator resin portion 24, the cover 61, and the connector portion 62 is lower than the heat of fusion of polybutylene terephthalate (PBT). By using resins with a relatively low heat of fusion for the housing 50, the stator resin portion 24, the cover 61, and the connector portion 62, the molten resin can easily melt portions of the annular protrusions provided on each portion when molding the molded resin portion 70. This allows each annular protrusion to effectively seal between the molded resin portion 70 and each portion, as described above. Furthermore, by making the shape of each annular protrusion in a cross section perpendicular to the direction in which the annular protrusion extends a substantially triangular shape whose width decreases with increasing distance from the surface on which the annular protrusion is provided, the tip of each annular protrusion can be more easily melted.

[0099] In this embodiment, as described above, the first annular protrusion 54, the second annular protrusion 25, the third annular protrusion 63, and the fourth annular protrusion 64 are provided, thereby enabling favorable sealing between the portions where the annular protrusions are provided and the molded resin portion 70. This facilitates ensuring a seal within the substrate accommodating portion 90 and the pump accommodating portion 52, even when the molded resin portion 70 is downsized in the axial direction. Furthermore, by radially overlapping the tubular housing portion 51 and the tubular cover portion 61b and fitting the lower end of the tubular cover portion 61b into the annular groove 24f, it is possible to form complex labyrinth shapes at the boundaries between the components extending from the exterior to the interior of the substrate accommodating portion 90 and the boundaries between the components extending from the interior of the pump accommodating portion 52 to the exterior of the electric pump 100. This facilitates ensuring a seal within the substrate accommodating portion 90 and the pump accommodating portion 52, even when the molded resin portion 70 is downsized in the axial direction.

[0100] The resin that constitutes the housing 50, the stator resin portion 24, the cover 61, and the connector portion 62 is, for example, syndiotactic polystyrene (SPS). In this embodiment, the resins that constitute the housing 50, the stator resin portion 24, the cover 61, and the connector portion 62 are the same. In this embodiment, the resin that constitutes the molded resin portion 70 is the same as the resin that constitutes the housing 50, the stator resin portion 24, the cover 61, and the connector portion 62. Note that the resins that constitute the housing 50, the stator resin portion 24, the cover 61, the connector portion 62, and the molded resin portion 70 may be different from one another.

[0101] As shown in Fig. 8 , a worker or the like manufacturing the electric pump 100 of the present embodiment fixes the circuit board 95 to the stator assembly 20, and then brings the cover assembly 60 close from above the stator assembly 20. As shown in Fig. 9 , the worker or the like fits the lower end of the cover cylindrical portion 61b into the annular groove 24f, and places the cover assembly 60 above the stator assembly 20. At this time, the worker or the like presses the second terminal portion 65b, which is a press-fit terminal, into the hole portion 95b of the circuit board 95 to electrically connect the connector terminal 65 and the circuit board 95.

[0102] As shown in FIG. 9, the worker or the like brings the rotor 10, which is integrally connected to the pump section 40, close to the stator assembly 20 from below. As shown in FIG. 10, the worker or the like passes the fixed shaft 30 through the bearing section 15 and positions the rotor 10 radially inside the stator 20a. At this time, the rotor 10 is held radially inside the stator 20a by the magnetic force of the magnet 12. The worker or the like brings the washer 32 close from below the fixed shaft 30 and passes the fixed shaft 30 inside the washer 32. For example, a highly viscous grease is applied to the inside of the washer 32, and the viscosity of the grease prevents the washer 32 from falling down from the fixed shaft 30.

[0103] As shown in FIG. 10 , an operator places an assembly 100a, in which the circuit board 95, the cover assembly 60, the rotor 10, the pump unit 40, and the washer 32 are assembled to the stator assembly 20, into the housing 50 through the upper opening of the housing 50. At this time, the operator presses the stator resin part 24 radially inside the cylindrical housing part 51. At this time, the operator also inserts the protrusion 55 provided on the inner peripheral surface of the cylindrical housing part 51 into the recess 24e provided on the outer peripheral surface of the stator resin part 24. The operator presses the assembly 100a including the stator assembly 20 radially inside the cylindrical housing part 51 until the fourth step surface 24g of the stator resin part 24 contacts the first step surface 51e of the cylindrical housing part 51.

[0104] As shown in FIG. 11 , an operator places an assembly 100b, which is formed by placing the assembly 100a inside the housing 50, inside a mold M. The assembly 100b is an assembly that includes all components constituting the electric pump 100 except for the molded resin portion 70. The mold M has a cavity C for molding the molded resin portion 70. The mold M has multiple gates G above the radially inner end of a portion of the cavity C for molding the resin lid portion 71. An operator pours molten resin R through the gate G into the cavity C. The resin R poured into the cavity C from the gate G flows radially outward through a portion of the cavity C located above the lid portion 61a and then flows into a portion of the cavity C located radially outward of the cylindrical cover portion 61b. The resin R fills the cavity C and hardens, thereby molding the molded resin portion 70. As a result, the housing 50, the cover 61, and the stator resin portion 24 are connected by the molded resin portion 70, and the electric pump 100 is manufactured.

[0105] Below, embodiments different from the above-described embodiments will be described. In the following description of each embodiment, the same configurations as those described above in the description of each embodiment may be omitted by appropriately assigning the same reference numerals. Furthermore, parts corresponding to the respective parts of the configurations described above in the description of each embodiment may be assigned the same names but different reference numerals, and differences from the above-described configurations may be described, while similar configurations to the above-described configurations may be omitted. Note that, as the configurations whose description is omitted in each of the following embodiments, configurations similar to the configurations described above in the description of each embodiment may be adopted within the scope of not being inconsistent.

[0106] Second Embodiment As shown in FIG. 12 , in the cover assembly 260 of the electric pump 200 of this embodiment, the connector portion 262 protrudes upward from a portion of the upper surface of the lid portion 61a of the cover 61 that is located radially inward from the inner edge of the resin lid portion 71. The connector portion 262 has a connector tubular portion 262b. The connector tubular portion 262b is tubular and opens upward. A central axis J runs through the inside of the connector tubular portion 262b. A lower end of the connector tubular portion 262b is connected to the upper surface of the lid portion 61a. A connector terminal 265 is partially embedded in the connector tubular portion 262b to hold the connector terminal 265. In this embodiment, the connector terminal 265 extends in the axial direction. The connector terminal 265 axially penetrates from the inside of the connector tubular portion 262b through a bottom portion on the lower side of the connector tubular portion 262b and is electrically connected to the circuit board 95. The other configurations of the cover assembly 260 are similar to the other configurations of the cover assembly 60 in the first embodiment.

[0107] The housing 250 is similar to the housing 50 in the first embodiment, except that the housing cylindrical portion 251 does not have the through-hole 51i. The molded resin portion 270 is similar to the molded resin portion 70 in the first embodiment, except that it does not have a portion that comes into contact with the connector portion 262, such as the protruding resin portion 74. The other configurations of the electric pump 200 are similar to the other configurations of the electric pump 100 in the first embodiment.

[0108] Third Embodiment As shown in FIG. 13 , in the electric pump 300 of this embodiment, the cover 361 does not have the cylindrical cover portion 61b, unlike the cover 61 of the first embodiment. The cover 361 has a first recess 361c. In this embodiment, the first recess 361c is recessed downward from the upper surface of the lid portion 361a. The first recess 361c has, for example, an annular shape surrounding the central axis J. A plurality of first recesses 361c may be provided at intervals in the circumferential direction. The inner surface of the first recess 361c has a surface facing upward, a surface facing radially inward, and a surface facing radially outward. The other configurations of the cover 361 are similar to those of the cover 61 of the first embodiment.

[0109] The upper end surface of the housing cylindrical portion 351 of the housing 350 contacts the lower surface of the radially outer edge portion of the lid portion 361a. The housing 350 has a second recess 351p. In this embodiment, the second recess 351p is recessed radially inward from the outer peripheral surface of the housing cylindrical portion 351. The second recess 351p is, for example, annular and surrounds the central axis J. A plurality of second recesses 351p may be provided at intervals in the circumferential direction. The second recess 351p is provided below and away from the upper end of the housing cylindrical portion 351. The inner surface of the second recess 351p has a surface facing radially outward, a surface facing upward, and a surface facing downward. The other configurations of the housing 350 are similar to those of the housing 50 in the first embodiment.

[0110] The molded resin portion 370 includes a first resin portion 371 and a second resin portion 372. The first resin portion 371 contacts a radially outer portion of the upper surface of the lid portion 361a. The first resin portion 371 is annular and surrounds the central axis J. The second resin portion 372 protrudes downward from the radially outer edge of the first resin portion 371. The second resin portion 372 is cylindrical and surrounds the central axis J. The second resin portion 372 is located radially outward from the lid portion 361a and the cylindrical housing portion 351. The second resin portion 372 surrounds the lid portion 361a and the cylindrical housing portion 351. The inner circumferential surface of the second resin portion 372 contacts the radially outer surface of the lid portion 361a and the outer circumferential surface of the cylindrical housing portion 351. The lower end of the second resin portion 372 is located below the second recess 351p.

[0111] The molded resin part 370 has a first protrusion 371b, which is a portion located within the first recess 361c, and a second protrusion 371c, which is a portion located within the second recess 351p. This allows the molded resin part 370 to come into contact with the inner surfaces of the first recess 361c and the second recess 351p. This increases the contact area between the molded resin part 370 and the housing 350, and the contact area between the molded resin part 370 and the cover 361. This allows the molded resin part 370 to more firmly connect the housing 350 and the cover 361.

[0112] The first convex portion 371b protrudes downward from the lower surface of the first resin portion 371. The first convex portion 371b fills the entire interior of the first recess 361c. The first convex portion 371b contacts the entire inner surface of the first recess 361c. The second convex portion 371c protrudes radially inward from the inner circumferential surface of the second resin portion 372. The second convex portion 371c fills the entire interior of the second recess 351p. The second convex portion 371c contacts the entire inner surface of the second recess 351p.

[0113] Other configurations of the electric pump 300 are similar to other configurations of the electric pump 100 in the first embodiment.

[0114] <Fourth embodiment> As shown in FIG. 14, in the electric pump 400 of this embodiment, the cover 461 does not have the cylindrical cover portion 61b, unlike the cover 61 of the first embodiment. The cover 461 has a second through hole 461d that penetrates a part of the cover 461 in the axial direction. In this embodiment, the second through hole 461d penetrates the lid portion 461a in the axial direction. For example, a plurality of second through holes 461d are provided at intervals in the circumferential direction. The other configuration of the cover 461 is similar to the other configuration of the cover 61 of the first embodiment.

[0115] The housing 450 has a flange portion 458 that protrudes radially outward from the upper end of the housing cylindrical portion 451. The flange portion 458 is annular and surrounds the central axis J. The upper surface of the flange portion 458 contacts the lower surface of the lid portion 461a. The radial outer edge of the flange portion 458 is located at the same radial position as the radial outer edge of the lid portion 461a.

[0116] The housing 450 has an extension portion 459 extending in the axial direction. The extension portion 459 is passed through the second through hole 461d from below. In this embodiment, the extension portion 459 protrudes upward from the upper surface of the flange portion 458. The upper end of the extension portion 459 is located higher than the upper surface of the lid portion 461a. In other words, the extension portion 459 has a portion located higher than the second through hole 461d. The extension portion 459 is provided away from the inner surface of the second through hole 461d. The extension portion 459 may contact the inner surface of the second through hole 461d. For example, a plurality of extension portions 459 are provided at intervals in the circumferential direction. The plurality of extension portions 459 are passed through the plurality of second through holes 461d in the axial direction, respectively.

[0117] The extending portion 459 has a third through hole 459a that penetrates the extending portion 459 in a direction perpendicular to the axial direction. In the present embodiment, the third through hole 459a penetrates the extending portion 459 in the radial direction. The third through hole 459a is provided in a portion of the extending portion 459 that is positioned above the second through hole 461d. In other words, the portion of the extending portion 459 that is positioned above the second through hole 461d has the third through hole 459a that penetrates the extending portion 459 in a direction perpendicular to the axial direction.

[0118] The molded resin portion 470 has a first resin portion 471, a second resin portion 472, and a third resin portion 475. The first resin portion 471 contacts a radially outer portion of the upper surface of the lid portion 461a. The first resin portion 471 is annular and surrounds the central axis J. A radially inner edge portion of the first resin portion 471 is located radially inward of the second through hole 461d. The first resin portion 471 has a base portion 471d and a protruding portion 471e. The base portion 471d contacts the upper surface of the lid portion 461a. The protruding portion 471e protrudes upward from the base portion 471d. The protruding portion 471e overlaps with the extension portion 459 and the second through hole 461d when viewed in the axial direction.

[0119] The second resin portion 472 protrudes downward from the radial outer edge portion of the first resin portion 471. The second resin portion 472 is cylindrical and surrounds the central axis J. The second resin portion 472 is located radially outside the lid portion 461a and the flange portion 458. The second resin portion 472 surrounds the lid portion 461a and the flange portion 458. The inner circumferential surface of the second resin portion 472 contacts the radially outer surface of the lid portion 461a and the radially outer surface of the flange portion 458.

[0120] The third resin portion 475 protrudes radially inward from the lower end of the second resin portion 472. The third resin portion 475 is annular and surrounds the central axis J. The third resin portion 475 contacts a radially outer portion of the lower surface of the flange portion 458. The third resin portion 475 does not necessarily have to be provided.

[0121] The portion of the extension portion 459 where the third through hole 459a is provided is embedded in the molded resin portion 470. Therefore, a portion of the molded resin portion 470 is provided inside the third through hole 459a, and the molded resin portion 470 contacts the inner surface of the third through hole 459a. This increases the contact area between the molded resin portion 470 and the housing 450, thereby more firmly fixing the molded resin portion 470 to the housing 450. Furthermore, the third through hole 459a is provided in the portion of the extension portion 459 that passes through the second through hole 461d and protrudes upward. Therefore, the portion of the extension portion 459 where the third through hole 459a is provided is embedded in the molded resin portion 470, thereby preventing the extension portion 459 from slipping downward through the second through hole 461d. This allows the molded resin portion 470 to more firmly fix the cover 461 to the housing 450.

[0122] In this embodiment, the portion of extension portion 459 located above second through hole 461d is entirely embedded in molded resin portion 470. The portion of extension portion 459 located above second through hole 461d is embedded across base portion 471d and protrusion 471e. Molded resin portion 470 has a portion that fills the gap between the inner surface of second through hole 461d and extension portion 459. This makes it possible to prevent cover 461 from shifting radially relative to housing 450.

[0123] Other configurations of the electric pump 400 are similar to other configurations of the electric pump 100 in the first embodiment.

[0124] The present invention is not limited to the above-described embodiment, and other configurations and methods may be adopted within the scope of the technical concept of the present invention. The molded resin portion may have any shape as long as it contacts at least a portion of the housing and at least a portion of the cover and connects the housing and the cover. The molded resin portion may not contact the stator resin portion and may not connect the stator resin portion to the housing and the cover. The housing may not be made of resin. The housing may be made of metal, for example. The housing may not have a cylindrical housing portion. In this case, the molded resin portion may connect the pump accommodating portion of the housing and the cover. The cover may not be made of resin. The cover may be made of metal, for example. The stator resin portion may not be provided.

[0125] The use of the pump to which the present invention is applied is not particularly limited. The pump may be mounted on any type of equipment. For example, the pump may be mounted on a vehicle. The pump may be a pump that pumps any type of fluid. The pump may be an oil pump that pumps oil.

[0126] The present technology can be configured as follows. (1) An electric pump comprising: a rotor rotatable about a central axis; a stator located radially outward of the rotor; a pump section connected to one axial side of the rotor; a circuit board located on the other axial side of the stator; a housing having a pump accommodating section that accommodates the pump section therein; a cover that covers the circuit board from the other axial side; and a molded resin section that contacts at least a portion of the housing and at least a portion of the cover and connects the housing and the cover. (2) The electric pump according to (1), wherein the molded resin portion fills the gap between the housing and the cover around the central axis. (3) An electric pump as described in (1) or (2), wherein the housing has a housing cylindrical portion that surrounds the stator from the radial outside and opens to the other axial side, and at least a portion of the housing cylindrical portion that is located on the other axial side of the stator contacts the molded resin portion, and the molded resin portion connects the housing cylindrical portion to the cover. (4) An electric pump as described in (3), wherein at least a portion of the cylindrical housing portion located on the other axial side of the stator is embedded in the molded resin portion, and the cylindrical housing portion has a first through hole that penetrates the cylindrical housing portion from its inner surface to its outer surface in the portion embedded in the molded resin portion. (5) An electric pump as described in (3) or (4), wherein the cover has a lid portion located on the other axial side of the circuit board and a cover cylindrical portion protruding from the lid portion on one axial side, at least a portion of the cover cylindrical portion being located radially inside the housing cylindrical portion, and the molded resin portion connecting the housing cylindrical portion and the cover cylindrical portion. (6) An electric pump as described in (5), wherein the molded resin portion contacts the outer peripheral surface of the cover cylindrical portion, the inner peripheral surface of the housing cylindrical portion, the outer peripheral surface of the housing cylindrical portion, the other axial side surface of the lid portion, and the other axial side end face of the housing cylindrical portion. (7) An electric pump as described in (5) or (6), wherein the end portion on the other axial side of the cylindrical housing portion is located at the same axial position as the surface on the other axial side of the cover portion, or is located on one side of the surface on the other axial side of the cover portion. (8) An electric pump described in any one of (5) to (7), wherein an annular stepped surface surrounding the central axis and facing the other axial side is provided on the inner peripheral surface of the cylindrical housing portion, the housing has a first annular protrusion protruding from the stepped surface to the other axial side and is made of resin, the first annular protrusion is annular and surrounding the central axis and is embedded in the molded resin portion. (9) An electric pump described in any one of (1) to (8), comprising a stator resin portion in which at least a portion of the stator is embedded, the molded resin portion contacting at least a portion of the stator resin portion and connecting the housing, the cover, and the stator resin portion. (10) An electric pump described in any one of (5) to (8), comprising a stator resin portion in which at least a portion of the stator is embedded, the molded resin portion contacting at least a portion of the stator resin portion and connecting the housing, the cover, and the stator resin portion, the stator resin portion having a stator resin main body portion having a portion covering the stator from the other axial side, the circuit board being positioned axially between the stator resin main body portion and the lid portion, and an end portion on one axial side of the cover cylindrical portion contacting the stator resin main body portion from the other axial side. (11) The electric pump described in (10) has an annular groove recessed from the surface of the stator resin main body on the other axial side to one axial side and surrounding the central axis, and an end portion on one axial side of the cover cylindrical portion is fitted into the annular groove. (12) The electric pump described in (10) or (11), wherein the stator resin portion has a first annular resin portion that is annular and surrounds the central axis, the first annular resin portion covers the radially outer surface of the stator over the entire circumference around the central axis, and the first annular resin portion is fitted to the radially inner side of the housing cylindrical portion. (13) The electric pump described in (12), wherein the inner circumferential surface of the cylindrical housing has an inner circumferential surface portion that is spaced radially outward from the outer circumferential surface of the first annular resin portion, the inner circumferential surface portion being located on the other axial side of the portion of the inner circumferential surface of the cylindrical housing with which the first annular resin portion is fitted, and the molded resin portion has a portion filled radially between the inner circumferential surface portion and the outer circumferential surface of the first annular resin portion. (14) An electric pump described in any one of (10) to (13), wherein the molded resin portion contacts the outer peripheral surface of the cover cylindrical portion, the inner peripheral surface of the housing cylindrical portion, the outer peripheral surface of the housing cylindrical portion, the other axial side surface of the lid portion, the other axial side end face of the housing cylindrical portion, the other axial side surface of the stator resin main body portion, and the radially outer surface of the stator resin main body portion. (15) An electric pump described in any one of (10) to (14), wherein the stator resin portion has a second annular protrusion that protrudes toward the other axial direction from a portion of the other axial surface of the stator resin main body portion that is located radially outside the cover cylindrical portion, and the second annular protrusion is annular and surrounds the central axis, and is embedded in the molded resin portion. (16) An electric pump described in any one of (10) to (15), wherein the molded resin portion has a portion that contacts the other axial surface of the lid portion, the cover has a third annular protrusion that protrudes from the other axial surface of the lid portion to the other axial side, and is made of resin, and the third annular protrusion is annular and surrounds the central axis, and is embedded in the molded resin portion. (17) The electric pump according to (16), wherein a plurality of the third annular projections are provided at intervals in the radial direction. (18) The electric pump described in (16) or (17), wherein the molded resin portion has a second annular resin portion that is annular and surrounds the central axis, the second annular resin portion is located radially outside the cover cylindrical portion, and a gate mark is provided on the other axial side surface of the molded resin portion, and the gate mark is located radially inside the third annular protrusion. (19) An electric pump described in any one of (1) to (18), wherein the cover has a second through hole that penetrates a portion of the cover in the axial direction, the housing has an extension portion that extends in the axial direction and passes through the second through hole from one axial side, the extension portion has a portion that is located on the other axial side of the second through hole, the portion of the extension portion that is located on the other axial side of the second through hole has a third through hole that penetrates the extension portion in a direction perpendicular to the axial direction, and the portion of the extension portion where the third through hole is provided is embedded in the molded resin portion. (20) An electric pump according to any one of (1) to (19), wherein the cover has a first recess, the housing has a second recess, and the molded resin portion has a portion located within the first recess and a portion located within the second recess.

[0127] The configurations and methods described in this specification can be combined as appropriate within the scope of not being mutually contradictory. [Explanation of symbols]

[0128] 10...rotor, 20a...stator, 24...stator resin portion, 24b...first annular resin portion, 24e...recess, 24f...annular groove, 24s...stator resin main body portion, 25...second annular protrusion, 40...pump portion, 50, 250, 350, 450...housing, 51, 251, 351, 451...housing cylindrical portion, 51g...third stepped surface (stepped surface), 51h...first through hole, 51k...inner peripheral surface portion, 52...pump accommodating portion, 54...first annular protrusion, 61, 36 1,461...Cover, 61a, 361a, 461a...Lid portion, 61b...Cylindrical cover portion, 63, 63a, 63b...Third annular protrusion, 70, 270, 370, 470...Molded resin portion, 71a...Gate mark, 72...Second annular resin portion, 95...Circuit board, 100, 200, 300, 400...Electric pump, 351p...Second recess, 361c...First recess, 459...Extension portion, 459a...Third through hole, 461d...Second through hole, G...Gate, J...Central axis

Claims

1. a rotor rotatable about a central axis; a stator positioned radially outside the rotor; a pump portion connected to one axial side of the rotor; a circuit board located on the other axial side of the stator; a housing having a pump accommodating portion that accommodates the pump portion therein; a cover that covers the circuit board from the other axial side; a molded resin portion that contacts at least a portion of the housing and at least a portion of the cover and connects the housing and the cover; An electric pump.

2. The electric pump according to claim 1 , wherein the molded resin portion fills the gap between the housing and the cover over a circumference around the central axis.

3. the housing has a cylindrical housing portion that surrounds the stator from the radial outside and opens to the other axial side, At least a part of a portion of the housing cylindrical portion that is located on the other axial side of the stator contacts the molded resin portion, The electric pump according to claim 1 , wherein the molded resin portion connects the cylindrical housing portion and the cover.

4. At least a part of the cylindrical housing portion, which is located on the other axial side of the stator, is embedded in the molded resin portion, The electric pump according to claim 3 , wherein the cylindrical housing portion has a first through-hole that penetrates the cylindrical housing portion from an inner peripheral surface to an outer peripheral surface at a portion embedded in the molded resin portion.

5. The cover is a cover portion located on the other axial side of the circuit board; a cylindrical cover portion protruding from the lid portion toward one axial direction; and At least a portion of the cylindrical cover portion is located radially inside the cylindrical housing portion, The electric pump according to claim 3 , wherein the molded resin portion connects the cylindrical housing portion and the cylindrical cover portion.

6. 6. The electric pump according to claim 5, wherein the molded resin portion contacts an outer peripheral surface of the cylindrical cover portion, an inner peripheral surface of the cylindrical housing portion, an outer peripheral surface of the cylindrical housing portion, a surface on the other axial side of the lid portion, and an end face on the other axial side of the cylindrical housing portion.

7. 6. The electric pump according to claim 5, wherein the end portion on the other axial side of the cylindrical housing portion is located at the same axial position as the surface on the other axial side of the cover portion, or is located on one axial side of the surface on the other axial side of the cover portion.

8. an annular stepped surface that surrounds the central axis and faces the other axial direction is provided on an inner peripheral surface of the cylindrical housing portion; the housing has a first annular protrusion protruding from the stepped surface to the other axial side, and is made of resin; The electric pump according to claim 5 , wherein the first annular projection is annular and surrounds the central axis, and is embedded in the molded resin portion.

9. a stator resin portion in which at least a portion of the stator is embedded, The electric pump according to claim 1 , wherein the molded resin portion contacts at least a portion of the stator resin portion, and connects the housing, the cover, and the stator resin portion.

10. a stator resin portion in which at least a portion of the stator is embedded, the molded resin portion contacts at least a portion of the stator resin portion and connects the housing, the cover, and the stator resin portion; the stator resin portion has a stator resin main body portion having a portion covering the stator from the other axial side, the circuit board is located between the stator resin body and the lid in the axial direction, The electric pump according to claim 5 , wherein one axial end of the cylindrical cover portion contacts the other axial end of the stator resin body portion.

11. the stator resin body has an annular groove recessed from the surface on the other axial side of the stator resin body to one axial side and surrounding the central axis, The electric pump according to claim 10, wherein one axial end of the cylindrical cover portion is fitted into the annular groove.

12. the stator resin portion has a first annular resin portion that is annular and surrounds the central axis, the first annular resin portion covers a radially outer surface of the stator around the central axis, The electric pump according to claim 10 , wherein the first annular resin portion is fitted to a radially inner side of the cylindrical housing portion.

13. an inner circumferential surface of the housing cylindrical portion has an inner circumferential surface portion that is spaced radially outward from an outer circumferential surface of the first annular resin portion, the inner circumferential surface portion is located on the other axial side of a portion of the inner circumferential surface of the cylindrical housing portion, into which the first annular resin portion is fitted, The electric pump according to claim 12 , wherein the molded resin portion has a portion filled between the inner circumferential surface portion and the outer circumferential surface of the first annular resin portion in a radial direction.

14. 11. The electric pump according to claim 10, wherein the molded resin portion contacts an outer peripheral surface of the cover cylindrical portion, an inner peripheral surface of the housing cylindrical portion, an outer peripheral surface of the housing cylindrical portion, a surface on the other axial side of the lid portion, an end face on the other axial side of the housing cylindrical portion, a surface on the other axial side of the stator resin main body portion, and a radially outer surface of the stator resin main body portion.

15. the stator resin portion has a second annular protrusion that protrudes toward the other axial direction from a portion of the other axial side surface of the stator resin main body that is positioned radially outward from the cylindrical cover portion, The electric pump according to claim 10 , wherein the second annular projection is annular and surrounds the central axis, and is embedded in the molded resin portion.

16. the molded resin portion has a portion that contacts the other axial side surface of the lid portion, the cover has a third annular protrusion that protrudes from the other axial side surface of the lid portion to the other axial side, and is made of resin; The electric pump according to claim 10 , wherein the third annular projection is annular and surrounds the central axis, and is embedded in the molded resin portion.

17. The electric pump according to claim 16, wherein a plurality of the third annular projections are provided at intervals in the radial direction.

18. the molded resin portion has a second annular resin portion that is annular and surrounds the central axis, the second annular resin portion is located radially outward of the cylindrical cover portion, a gate mark is provided on the other axial surface of the molded resin portion; The electric pump according to claim 16, wherein the gate mark is located radially inward of the third annular protrusion.

19. the cover has a second through-hole that passes through a portion of the cover in the axial direction, the housing has an extension portion that extends in the axial direction and is passed through the second through hole from one axial side; the extension portion has a portion located on the other axial side of the second through hole, a portion of the extension portion located on the other axial side of the second through hole has a third through hole penetrating the extension portion in a direction perpendicular to the axial direction, The electric pump according to claim 1 , wherein a portion of the extension portion where the third through hole is provided is embedded in the molded resin portion.

20. the cover has a first recess; the housing has a second recess; The electric pump according to claim 1 , wherein the molded resin portion has a portion located within the first recess and a portion located within the second recess.

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